目的探讨原发性淋巴结外Rosai-Dorfman病(RDD)的临床病理学特征、诊断及鉴别诊断。方法分析3例结外Rosai-Dorfman病的临床特点,并行HE和免疫组化染色。结果 3例中男性1例,女性2例,年龄40~72岁,平均57岁。病变分别位于右鼻腔、左大腿皮下软组织及子宫内膜。组织学特点为组织细胞明显增生,细胞体积大,胞质丰富淡染,与间质内淋巴细胞和浆细胞形成(淡染、深染相间)类似淋巴窦隙样的结构,组织细胞胞质内可见吞噬的淋巴细胞、浆细胞。免疫组化示组织细胞S-100蛋白(+),部分CD163(+)。结论结外RosaiDorfman病较为少见,有特征性的病理学特点,系统累及可能性较小,预后较好,有一定的局部复发率。组织学上应与Langerhans细胞组织细胞增生症等鉴别。 Objective To investigate the clinicopathological features, diagnosis and differential diagnosis of Rosai-Dorfman disease (RDD) outside primary lymph nodes. Methods The clinical features of 3 cases of extranodal Rosai-Dorfman’s disease were analyzed. HE and immunohistochemical staining were performed. Results In 3 cases, there were 1 males and 2 females, aged from 40 to 72 years with an average of 57 years. Lesions were located in the right nasal cavity, left thigh subcutaneous soft tissue and endometrium. Histological features of obvious proliferation of tissue cells, large cell volume, rich in light cytoplasmic staining, and the formation of interstitial lymphocytes and plasma cells (lightly stained, dark-stained phase) similar to the structure of the lymphoid sinusoids, the cytoplasm of tissue cells Visible phagocytic lymphocytes, plasma cells. Immunohistochemistry showed that the tissue cells S-100 protein (+), partial CD163 (+). Conclusion The extracapsular RosaiDorfman disease is rare, with characteristic pathological features, less possibility of systemic involvement, better prognosis and certain local recurrence rate. Histologically, Langerhans cell histiocytosis should be identified.